[geek1011]

Update: This just got worse for me. I think I'll do a factory reset, then modify the Kobo scripts to do a non-lazy unmount.

An integrity check on the db:

sqlite> PRAGMA integrity_check;
*** in database main ***
On tree page 72 cell 3: Rowid 4052 out of order
Page 50803: btreeInitPage() returns error code 11
On tree page 72 cell 0: Rowid 3945 out of order
On tree page 46 cell 14: 2nd reference to page 50808
On tree page 26674 cell 0: 2nd reference to page 50803
On tree page 122 cell 40: 2nd reference to page 50835
On tree page 50671 cell 1: Rowid 4061 out of order
On tree page 50687 cell 1: Rowid 4046 out of order
On tree page 44 cell 4: 2nd reference to page 50837
Page 25140 is never used
Page 25155 is never used
Page 25156 is never used
Page 25157 is never used
Page 25158 is never used
Page 25159 is never used
Page 25160 is never used
Page 25161 is never used
Page 25162 is never used
Page 25164 is never used
Page 25166 is never used
Page 25167 is never used
Page 25169 is never used
Page 25170 is never used
Page 25171 is never used
Page 25172 is never used
Page 25173 is never used
Page 25174 is never used
Page 25180 is never used
Page 25219 is never used
Page 25220 is never used
Page 25222 is never used
Page 25224 is never used
Page 25286 is never used
Page 30885 is never used
Page 30886 is never used
Page 30887 is never used
Page 30889 is never used
Page 30890 is never used
Page 35858 is never used
Page 35860 is never used
Page 35861 is never used
Page 35862 is never used
Page 35866 is never used
Page 35867 is never used
Page 35868 is never used
Page 35869 is never used
Page 40327 is never used
Page 40328 is never used
Page 40329 is never used
Page 50041 is never used
Page 50098 is never used
Page 50432 is never used
Page 50447 is never used
Page 50463 is never used
Page 50464 is never used
Page 50524 is never used
Page 50670 is never used
Page 50703 is never used
Page 50830 is never used
Page 50913 is never used
Page 50914 is never used
Error: database disk image is malformed
sqlite> .recover
---db dump removed for brevity, but of interest is some rows which have disappeared since my last backup, and a few missing indices---

Some messages from dmesg on my laptop:

[83950.045837] VFS: busy inodes on changed media or resized disk sdd

There's nothing useful in the dmesg files left in the .kobo directory (and the recent ones were corrupted, then removed by the firmware [why, kobo :/] after they were recovered by fsck).